Sleep Apnea (SA) is the most common disorder observed in the practice of sleep medicine and is responsible for more mortality and morbidity than any other sleep disorder. Although more than 4% of the population is estimated to suffer from SA, the majority are undiagnosed and untreated. This proposal furthers the development of the Apnea Risk Evaluation System (ARES), an integrated system that includes: a) an acquisition device that can be easily self-applied to the forehead and comfortably worn throughout the night to collect high-quality physiological data to screen for SA (SpO2, pulse, snoring and head position), b) software designed to identify respiratory events and movement artifacts, c) a questionnaire to assess risk factors commonly associated with SA, and d) expert system logic to classify an individual's level of risk for SA. The proposed study is a continuation of a previous Phase I ARES study. These goals include: furthering the validation and testing of the ARES Profile Analysis and completing design and. calibration of the ARES Device in preparation for testing on human subjection. The ARES is designed to be an inexpensive, self- applied, in-home method for assessment of risk for SA. PROPOSED COMMERCIAL APPLICATIONS: Sleep Apnea is a serious, prevalent, under-diagnosed, but treatable disorder, creating a significant market demand for accurate, inexpensive and easy-to-administer assessment methods. The ARES will be marketed to Managed care providers, HMOs and other medical professionals, including those involved with Occupational and Industrial Medicine and epidemiology. The ARES will also be marketed directly-to-consumers as an in-home risk assessment for SA.